A standard gas appliance such as a smoker's lighter has a housing, a reservoir of a gasifiable combustible in the housing, and a nozzle in the housing connected to the reservoir and provided with a valve openable for emitting an ignitable stream of the combustible. A piezoelectric igniter in the housing has a relatively stationary generator part connected to an electrode at the nozzle and a relatively movable generator part connected to another electrode adjacent the nozzle electrode and movable on the stationary part to generate a potential between the electrodes. The stationary part can normally move somewhat to open the valve of the reservoir just before the spark is generated.
In such an appliance as described in U.S. Pat. No. 3,439,995 of H. Tadamichi and German patent document 1,451,412 of Mellert a depressible element connected to the movable generator part opens the valve and generates a spark between the electrodes in that order as it is depressed. The spark ignites the stream of gas emitted by the nozzle and as long as the element remains depressed the valve will remain open and the flame will burn.
It is standard in such an arrangement for one of the electrodes to be formed by the nozzle itself, typically by making it at least partially of conductive material and connecting it to the generator terminal of the relatively fixed part. The other nozzle can be a conductive element fixed in the housing adjacent the nozzle and connected as described in French patent 2,573,616 of H. Sadoya by a flexible wire to the other terminal which is on the more movable part of the piezoelectric sparker. Such an arrangement is fairly complicated and difficult to manufacture, especially for a throwaway item like a cigarette lighter.
In Japanese patent 57,251/89 of Kokai the second electrode is engaged by a wiper on the more movable igniter part as same is depressed. Such a construction demands fairly tight tolerances to ensure proper electrical contact. The connection must be made without the structure blocking depression of the lighter button and without leaving such a gap that no current can flow. Obviously this high-tolerance construction again elevates manufacturing costs.